Brand: CASIO
Model: fx-100
Type: Scientific calculator
Picture: CASIO fx-100
Batteries: AA x 2
Lifetime: Introduced: unknown
Terminated: unknown
Notes: This calculator is very similar to the CASIO fx-82, with the following differences, a bigger display with more digits, SCI, NORM and ENG modes, rounding, random number generation and a fraction key. Also functionally very similar to the CASIO fx-350, which has less digits but does hyperbolic trigonometric operations. Similar to the CASIO fx-82 series there is a collection of calculator in the fx-100 range. So far I’ve found mention of the following types:
  • CASIO fx-100 (this one)
  • CASIO fx-100A
  • CASIO fx-100AU
  • CASIO fx-100B
  • CASIO fx-100C
  • CASIO fx-100D
  • CASIO fx-100MS
  • CASIO fx-100MS-2
  • CASIO fx-100S
  • CASIO fx-100V

This calculator (as do many other CASIO scientific calculators) uses one and the same key for both the constant π as well as exponents. This works as follows. When you first enter digits, the "EXP"-key will enable you to enter the numbers exponent, otherwise it will enter the constant π.
Know what? This site can be helpful to some! Andrew Burge sent me this note:


I know someone in cyberspace would be collecting calculators - your site is great, well done.

Using your site I was able to work out where all the keys for my CASIO fx100 went after I took it to pieces to clean it ... and I didn't remember where the number keys went :)

I've used this calculator since I was at University and it still works well, you would think I would know where they keys go!

Best regards,

... Andrew